1. Field of the Invention
The present invention relates generally to pipes for transporting fluids, such as water, gas, chemical fluid and the like, and particularly to an acoustic leak detection system and method with environmental noise isolation, applicable to pipes and couplings, that generates an alert signal when a liquid leak from a pipe joint or coupling is detected.
2. Description of the Related Art
Pipelines suffer from leakage due to excess fluid pressure, corrosion caused by reactions with moving fluid or a surrounding medium, cracks due to aging, poor construction, poor maintenance or the like. Pipeline leakage may present serious environmental and economic problems. Thus, leaks should be quickly detected, located and repaired.
Typical conventional pipeline leak detection systems are relatively inefficient in terms of response time, sensitivity, robustness and cost. Pipeline leaks are typically detected by observation of the external effects of the spill, or by monitoring and analysis of the internal hydraulics of the pipeline. Neither of these methods provides real-time monitoring of the leak itself, only the indirect effects of a leak. One of the objectives of a pipeline leak detection system is to alert operators so that the size of the spill can be limited.
A wide variety of methods of leak detection are known, such as ultrasonic, electromagnetic, optical fiber, and acoustic-based methods. Typical acoustic detection methods suffer from location in noisy environments, i.e., pipeline networks are often located in or near industrial environments, traffic roads, subways, airports or the like. In such noisy environments, acoustic noise generated by the leak is often masked by background noise, particularly at the early stage of leakage when the acoustic signal of the leak is weakest. In such circumstances, the leak signal to noise ratio becomes considerably small.
It thus becomes necessary to isolate the acoustic signal generated by the leak from external or environmental noise. Thus, an acoustic leak detection system and method with environmental noise isolation solving the aforementioned problems is desired.